Hey ya fella. I had this problem from two days ago and today I found the solution. You should disable some of your extensions to make FF run better. I don't know what extension exactly is the cause but I can think the FoxyProxy maybe.

Try with each of 'em.

Hey ya fella. I had this problem from two days ago and today I found the solution. You should disable some of your extensions to make FF run better. I don't know what extension exactly is the cause but I can think the FoxyProxy maybe.
Try with each of 'em.